Deadlock Nightlatch Key Stiff when mounting screws tightened

[Rake722]

Hi All.

This lock used to work well until one day we tried to open the front door and the nightlatch fell off leaving us locked out.

We gained access and found the nightlach had come off its mounting plate. We put it back on and noticed it didn’t sit flush to the door on one side.

We adjusted the 2 tabs that the 2 mounting screws attach to on the night latch mounting plate and it then became stiff to open by key and internal lever.

If I slacking off the two mounting screws, the lever becomes easy to operate but start binding again when I tighten the two mounting screws down.

If I leave the screws loose and slam the door shut the internal lever becomes stiff again as it binds on the strike plate possibly because the night latch isn’t sitting flat on the inside of the door ??

Any help gratefully received

 

[footprints]

Often it is because the cylinder is being pulled slightly off centre as you tighten, they can be a pain to get spot on I suggest returning the plate to the original place, it may have been off centre before but was not noticed.

 

[Rake722]

Often it is because the cylinder is being pulled slightly off centre as you tighten, they can be a pain to get spot on I suggest returning the plate to the original place, it may have been off centre before but was not noticed.

Thanks for the reply. The place hasn’t been moved. It’s just the two little tongues that have the threads for the mountain screws have been adjusted.

I hope this doesn’t mean I need to get a new night latch

 

[footprints]

The tabs are attached to the backplate, which sets the position of the cylinder in relation to the lock if it is off centre that can cause the problem

 

[Rake722]

The tabs are attached to the backplate, which sets the position of the cylinder in relation to the lock if it is off centre that can cause the problem

I guess it’s a game of trial and error to find the right position for them then?

 

[footprints]

The latch is usually supplied with a paper template to get the large hole for the cylinder and backplate perfectly aligned, trouble is when a latch is replaced they don't always have the same dimensions. Either yours was replaced at some point or the installer was too clever to use the template!

 

[Rake722]

Yes understood. It was working before though. Only difference is that we have had builders on site. I wonder if they banged it or something. I’ll try and adjust those tabs a bit and see

 

[Rake722]

A couple of tweaks to the mounting plate and all good again

 

[footprints]

Glad you are sorted, thank you for the update.

 

[Rake722]

Glad you are sorted, thank you for the update.

I try to leave the outcome in case it helps others.
To be precise I user a wrench to adjust the angle of the 2 ears that the latch screws on to on the mounting plate until I found the angle at which the lock no longer binds.